TAMPA — How many dead boys are buried at the state's oldest reform school, and where are their remains located? Those are the questions that continue to baffle the families of the dead and former wards of the Marianna facility.

On Friday, Sen. Bill Nelson called on state officials to allow forensic anthropologists from the University of South Florida to continue to search for the clandestine graves of inmates at the reform school in the Panhandle town of Marianna. He also asked state legislators to fund the university's mission to locate and exhume the remains, and to determine how the boys died.

"Where there's smoke, there's fire," said Nelson, flanked by the families of two boys who died while imprisoned at the infamous facility, known through the years as the Florida School for Boys and the Dozier School for Boys. "I want them exhumed. I want them examined."

The researchers, led by USF professor Erin Kimmerle, examined one known cemetery using ground-penetrating radar and found at least 50 possible graves, 19 more than Florida Law Enforcement Investigators identified in an earlier investigation.

Kimmerle's team has asked for $160,000 from the state to continue field work. She said researchers are looking for a second cemetery, on the south side of the campus, using ground-penetrating radar. The state has given them permission to search for five more months. She said Attorney General Pam Bondi is supporting the project, along with Dr. Michael Hunter, the medical examiner for the region.

Some of the boys died under mysterious circumstances, including the two boys whose family members joined Nelson for the press conference. Ovell Krell's brother, Owen Smith, 14 at the time he was committed in 1940, was found decomposed under a house in Marianna after reportedly running away. But Krell, 12 at the time, heard from another state ward who saw her brother running across a field as men fired rifles at him.

"At 14 years old, at the end of January, you don't lay down under a house and freeze to death," said Krell, a former Lakeland police officer. "You get help."

Glen Varnadoe's uncle, Thomas, was sent to the school in 1934, at the age of 13. He was healthy when he left home, but he died 35 days later. School records say he died of pneumonia, but Varnadoe doubts that.

"We want to get to the bottom of this," Nelson said, adding that he has asked the Department of Justice to help if evidence shows the boys were killed. "I'm just here to make sure this investigation continues."

Ben Montgomery can be reached at bmontgomery@tampabay.com or (727) 893-8650.